Chapter 10 Drugs © 2013 McGraw-Hill Education. All Rights Reserved.1.

Chapter 10

Drugs

© 2013 McGraw-Hill Education. All Rights Reserved. 1

Who Uses? Patterns of Illicit Drug Use

• Rates of illicit drug use vary by age, gender, race and ethnicity, education, employment status, and geographical region

• Among Americans aged 12 or older, more than 47 percent report having used an illicit drug in their lifetime

• The most commonly used drug is marijuana• There is also a substantial misuse of

psychotherapeutics (prescription-type drugs)


Who Uses? Patterns of Illicit Drug Use

• College students who abuse prescription drugs increased dramatically between 1993 and 2005

– Pain relievers (e.g., OxyContin, Vicodin, Percocet): use increased by 343 percent

– Stimulants (e.g., Ritalin, Adderall): use increased by 93 percent

– Tranquilizers (e.g., Xanax, Valium): use increased by 450 percent

– Sedatives (e.g., Nembutal, Seconal): use increased by 225 percent


Illicit Drug Use in Past Month


Illicit drug use in past monthamong persons aged 12 or older: percentages, 2010.

Illicit Drug Use by Age


Illicit drug use by age, 2009 and 2010.

What Is a Drug?

• Drug: substance other than food that affects the structure or function of the body through its chemical action

• Drug of abuse: medical drug used for nonmedical (recreational) purposes, or a drug that has no medical uses

• Substance: drug of abuse, a medication, or a toxin; the term is used interchangeably with drug

• All drugs have the potential to be toxic, poisonous, dangerous, or deadly


Types of Drugs

• Drugs are classified in several different ways

• Legal drugs include:– Medication prescribed by physicians– Over-the-counter (OTC) medications– Herbal remedies

• Pharmaceutical drugs are developed for medical purposes, whether over-the-counter or prescription

• Illicit drugs are unlawful to possess, manufacture, sell, or use


Drug Misuse and Abuse

• Drug misuse: use of prescription drugs for purposes other than those for which they were prescribed or in greater amounts than prescribed, or the use of nonprescription drugs or chemicals for purposes other than those intended by the manufacturer

• Drug abuse: use of a substance in amounts, situations, or a manner such that it causes problems, or greatly increases the risk of problems, for the user or for others


Routes of Administration

• Oral—most drugs are taken orally• Injection

– Involves a hypodermic syringe to deliver drug into the bloodstream by

• Intravenous injection

• Intramuscular injection

• Subcutaneous injection

• Inhalation: smoking or huffing• Application to mucous membranes• Application to skin



Routes of Administration

Factors Influencing the Effects of Drugs

• Characteristics of the drug– Chemical properties of the drug and its actions

• Characteristics of the person– Age– Gender– Body weight and mass– Physical condition– Mood– Experience with the drug– Expectations

• Characteristics of the situation– Environmental experience


Drug Dependence

• Dependence is a condition characterized by a strong craving for a drug and by compulsive use of the drug despite serious negative consequences

– Usually means that physiological changes have taken place in the brain and body chemistry

• Tolerance is reduced sensitivity to the effects of the drug

• Withdrawal symptoms are different for different drugs and lead to unpleasant feelings


Effects of Drugs on the Brain

• Many addictive drugs act on neurons in three brain structures:

– The ventral tegmental area (VTA) in the midbrain

– Nucleus accumbens

– Prefrontal cortex

• Neurons in these structures form a pathway referred to as the pleasure and reward circuit

• Addictive psychoactive drugs activate and cause surge in levels of dopamine and associated feelings of pleasure


Effects of Drugs on the Brain

• All or nearly all addictive drugs operate via the pleasure and reward circuit


The pleasure and reward circuit in the brain

Psychoactive Drugs: Classifications


Classification of psychoactive drugs.

Central Nervous System Stimulants

• Drugs that speed up activity in the brain and sympathetic nervous system

• Effects similar to the “fight or flight” reaction

• May stimulate movement, fidgeting, and talking, and produce intense feelings of euphoria and create a sense of well-being

• Examples:– Cocaine– Amphetamines– MDMA (ecstasy)– Caffeine and bath salts


Central Nervous System Depressants

• Slow down activity in the brain and sympathetic nervous system

• Can be deadly if misused, especially when mixed with alcohol

• CNS depressants carry a high risk of dependence

• Examples:– Barbiturates and hypnotics– Anti-anxiety drugs (benzodiazepines)– Rohypnol– GHB (gamma hydroxybutyrate)


Opioids

• Natural and synthetic derivatives of opium

• Long history of medical use for pain relief and treatment of diarrhea and dehydration

• Currently prescribed as pain relievers, anesthetics, antidiarrheal agents, and cough suppressants

• Examples include morphine, heroin, and synthetic opioids (OxyContin, Vicodin, Demerol, Percocet, and Percodan)

• Produce feelings of pleasure and block the sensation of pain


Opioids

• With low doses opioid users experience:

– Euphoria– Drowsiness– Constriction of the pupils– Slurred speech– Slowed movement– Impaired coordination, attention, and memory

• At high dosage users can experience depressed respiration, loss of consciousness, coma, and death

• Opioids have a high potential for dependence


Hallucinogens

• Also known as psychedelics

• Alter perceptions and thinking in characteristic ways

• Intensify and distort visual and auditory perceptions and produce hallucinations

• Examples:

– LSD (lysergic acid diethylamide)

– PCP (phencyclidine)

– Peyote


Inhalants

• Breathable chemical vapors that alter consciousness, producing a state that resembles drunkenness

• Examples: paint thinner, gasoline, glue, and spray-can propellant

• Active ingredients are all powerful toxins and carcinogens

• The most significant negative effect for chronic users is widespread and long-lasting brain damage


Cannabinoids

• Marijuana is the most widely used illicit drug in the United States– Derived from the hemp plant, Cannabis sativa– Active ingredient is delta-9-tetrahydrocannabinol

(THC)– Use produces mild euphoria, sedation, lethargy,

short-term memory impairment, distorted sensory perceptions, distorted sense of time, impaired coordination, and an increase in heart rate

• Researchers have found that THC has a variety of effects on the brain, perhaps accounting for some impairments in problem-solving and decision-making


Approaches to the Drug Problem

• Supply reduction strategies:

– Interdiction: interception of drugs before they get into the country

– Pressure on supplying countries to suppress production and exportation

– Prevent domestic production and selling via law enforcement



• Demand reduction strategies:

– Incarceration for drug-related crimes

• Half the people in U.S. prisons meet the diagnostic standards for alcohol/drug dependence or abuse

• Only 7–17% who need drug treatment receive it

– Prevention strategies

• Primary prevention: designed to reach and educate entire population

• Secondary prevention: focus on subgroups that are at greatest risk for use or abuse

• Tertiary prevention: target at-risk individuals rather than groups



• Demand reduction strategies:

– Drug treatment programs

• Narcotics Anonymous (NA)

• Treatment is more successful when the program lasts at least three months



• Harm reduction strategies:

– Focus on helping addicts reduce the harm associated with drug use

• Needle exchange programs

• Drug substitute programs (ex: methadone instead of heroin)

• Controlled availability

• Medicalization

• Decriminalization


Chapter 10 Drugs © 2013 McGraw-Hill Education. All Rights Reserved.1.

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